Improvement in stone-tools



UNITED STATES PATENT l OFFICE.

IRA CURTNER, OF DAYTON, OHIO, ASSIGNOR TO CEAS. A. GMP AND EDWIN S.FORGY, OF SAME PLACE.

'IMPROVEMENT IN sToNE-TooLS.

Spccl ation forming part of Lettere Patent No. 146,05 l, dated December30, 1873; application filed September 20, 1973.

Fo all whom it may concern:

Be it known that I, IEA GURTNER, of Dayton, in the county of Montgomeryand State of Ohio, have invented a new and valuable Imand it consists inthe construction and novel arran gement of the devices for securing 1n"place a removable blade with a recess, as hereinafter more fullydescribed.

In the accompanying drawings, the letter A designates the handle. Bindicates the removable blade, tapering on its upper or lower surface,or both of them, toward the ends from the central portion a, which isprovided in its under side with the central recess b. G designates aferrule, provided with a socket to' receive the end or tenori of thehandle A, a screw or key, c, being usually employed to secure theconnection. The upper end of the ferrule is provided with ascrew-thread, d, extending to a shoulder, c, and designed to engage withthe shank-socket of the T-coupling. At the end of the threaded portion asmall boss er projection, h, is provided to enter the recess b of theblade when the ferrule is screwed 4 home. l) represents the T-coupling.This consists of the shank-socket k, having a female screw-thread, andthe blade-socket l, rectangular in form, and arranged at right' angleswith the axis of the shank-socket. rEhe bladesocket is of greaterdiameter than the shanksocket usually, and its upper or outer wall m isdesigned to extend longitudinally for some distance on each side of theshank-socket to receive the parallel central portion or body a of theblade, thus materially strengthening the same and deadening thevibrations, as the blade is, by the pressure of the boss h of theferrule, when the latter is screwed home, brought rml y in contact withsaid wall. When the parts are screwed together, the end of theshank-socket is designed to t the shoulder e of the ferrule neatly andevenly, so that the joint of the cylindrical surfaces of the "two partswill be hardly perceptible. `At the same time the frictional contactserves to obviate, in great measure, the tendency of the parts to becomeloose by unscrewing. The blade-socket is designed to fit the bladeneatly on each side, but loosely on .the lower surface, so that it canbe easily and quickly removed in either direction.

What I claim as new, and desire to secure by Letters Patent, is

The combination, with the T-coupling having the blade socket b, andshanksocket k, of the screw-ferrule C, provided with the boss h, toenter a central recess in the blade, substantially as specied.

In testimony that I claim the above I have hereunto subscribed my namein the presence of two witnesses.

IRA OURTNER.

Witnesses PATRICK H. GUNGKEL, CEAS. A. GUMP.

